Research On Migration System And Configuration Relationship In The North Area Of Liaohe Eastern Depression

This paper firstly analyzed migration elements such as sand body, fault and unconformity and the configuration type of migration system and its controlling on the migration and accumulation of oil and gas through the integrated use of well logging,logging and seismic data.The paper established a method for determining migration path based on migration system by combining multi-factor analysis such as oil source,trap,tectonic setting and evolution,fluid potential.Liaohe Depression is a typical continental rift basin.Structure is complicated in the north of liaohe eastern Depression with diverse configuration relationship of migration system.Through the study of migration elements of research area, the development characteristics of sand body,fault and unconformity of the north of liaohe eastern Depression were ascertained,migration effectiveness of migration elements were analyzed.Sand body development degree of the west is better than that of the east.Sand body is connectictiy and sand body facilitates the migration of oil and gas.Cidong fault and niu 74 fault as two vertical oil source faults in the study area are open,respectively,and supply oil to ciyutuo district and qinglongtai area.The unconformity between the 1、2rd of shahejie formation and the 3rd of shahejie formation is upper conducting effective.The spatial configuration type of migration system are sand body and fault,sand body and unconformity,fault and fault,fault and unconformity and sand body-fault-unconformity configuration,which major faults and sand body configuration in the north of liaohe eastern Depression.The paper analyzed migration system’s configuration and its control action in the migration and accumulation of oil and gas in ciyutuo area.“Block splicing of migration analysis method”is proposed innovatively for the rift basin.That is a comprehensive analysis technology of oil and gas migration path from source to trap based on migration elements characteristic and migration effectiveness analysis and configuration relationship of migration system as a node.The paper researched the migration path in niuju area,ciyutuo area and qinglongtai area by restoring accumulation period of fluid potential and combining with the conducting effectiveness of migration system and the configuration relationship of conducting element.The effectiveness of migration elements and configuration relationship of migration elements determine the effectiveness of migration system.In the tectonic setting and fluid potential control,they control the migration and accumulation of oil and gas. Skeletal sand body with good connectivity and physical properties is a good channel for oil and gas migration along sand body,which decide the final location of hydrocarbon accumulation.Oil and gas are located in high tectonic fault position side for poor lateral sealing faults and good degree of lateral sealing faults are easy to form a rich reservoir.The open faults communicate oil source from oil source rocks and oil source from an oil source layer,causing the closure extent of hydrocarbon accumulation layers.Unconformity surface lithology configuration determines the unconformity surface’s conducting and trapping in the process of petroleum migration and accumulation.